13. Firewood
That expensive cord of firewood won’t do much good keeping you warm in winter if it’s left in your basement. In addition to potentially attracting pests, the humidity in your basement could make that wood damp—and far from ideal in order to start a fire.
14. Propane tanks
The temperature fluctuations from your basement make it an unwisely option for storing propane. Propane tanks can explode when left in extreme heat, so if your basement gets unseasonably warm, they could explode.
In one notable 1983 incident, in Buffalo, New York, six people—five of them firefighters—were killed and 70 more were injured from a fire and explosion caused by illegally stored propane.
